1. Field of the Invention
The present invention relates to methods and apparatus for treating foot ulcers. More particularly, the invention relates to methods and apparatus for applying positive and/or negative pressures to treat foot ulcers such as diabetic ulcers, arterial ulcers, venous stasis ulcers, pressure ulcers, and the like.
2. Description of the Related Art
Foot ulcers can be devastating—they are difficult to heal and are potentially limb-threatening. One of the difficulties is that a patient will often lose sensation in the area of an ulcer and, as a result, the patient tends to abuse the ulcer without notice. Foot ulcers, in particular, are troublesome because they are out of the patient's sight, especially when located on or near the patient's heel. Unseen and unfelt, the patient does not realize that the foot ulcer is colliding into a wheelchair, bedpost or the like. Consequently, the onset of a foot ulcer may place the foot at a significant risk for progression toward sepsis, gangrene and, ultimately, amputation.
Current treatment options for foot ulcers are varied, but all tend to be costly and traumatic; greater efficacy is thus desired. One of the most common treatment options is debridement of necrotic tissue followed by an attempt to physically close the ulcer, typically with sutures, skin grafts or the like. Unfortunately, many patients do not respond quickly, or at all, to such traditional treatment and the patient's condition often worsens. The resulting economic and emotional costs to the patient, and the patient's family, are staggering.
On the positive side, there have long been techniques available for promoting healthy circulation of body fluids. The concept of applying positive and/or negative pressure to help affect circulation is ancient, and many have sought to apply this concept to the foot in the form of inflatable boots that squeeze the foot and/or leg. Some have applied alternating positive and negative pressures, in a cyclic fashion, to first force blood out of the foot with positive pressure and then draw blood back into the foot with negative pressure. Recent products offered by Applicant under the trade designation “PLEXIPULSE” have provided intermittent compression, for a variety of indications, through pneumatic force externally applied to the foot. Such products are used, for example, to help prevent venous stasis and to promote circulation or to help treat and assist healing of cutaneous ulceration.
Another approach, for treatment of wounds, is represented by Applicant's products recently made commercially available under the trade designations “V.A.C.” or “VACUUM ASSISTED CLOSURE.” The “V.A.C.” products generally comprise the application of negative pressure directly to a wound site, either on a continuous or intermittent basis. Such therapy units direct negative pressure to the wound site through a disposable pad, which includes a wound dressing and associated tubing, filters and drainage receptacles. The dressing itself includes a porous foam dressing sized to fit within the wound, the tubing directs the negative pressure into the foam, and the combination is sealed into the wound with the use of an adhesive drape that overlaps the entire wound site as well as a margin of surrounding intact skin. This therapy is promising for treatment of pressure ulcers and chronic open wounds, including decubitus ulcers and diabetic ulcers.
Both of the above-described therapies are currently available as of the filing date of this present application; despite the availability of such progressive therapies, however, foot ulcers continue to present serious concerns for patients and caregivers. It is therefore a fundamental object of the present invention to advance upon the prior art by providing an improved method and apparatus for effecting intermittent pneumatic compression concurrently with vacuum assisted closure. Many additional problems, obstacles and challenges present in existing modalities for the treatment of foot ulcers will be evident to caregivers and others of experience and ordinary skill in the art.